Insulation blankets and panels have been used for many years for protection from fire for bulkheads, overheads, hulls and compartments of aircraft, ships and the like, as certain areas within these aircraft or ships are both a potential source of ignition and a potential leakage of a flammable liquid and/or gas. In these areas, it is not possible to separate the potential ignition sources and any such leakage which could lead to a possible in transit explosion and/or fire. Areas within these aircraft or ships in which this separation cannot be accomplished are defined as fire zones and are required by various governmental agencies to be separated from other areas of the aircraft or ships by fireproof fire walls. Under FAA (Federal Aeronautics Administration) regulations, fire proofing means being able to withstand exposure to heat and flame at least as well as steel, or being able to withstand exposure to a 2000.degree. F. flame for 15 minutes without flame penetration. In ships, the typical level of protection required is 60 minutes when exposed to heat conditions prescribed by the ASTM E119 standards or the U.S. Coast Guard A60 criterion, as provided by the International Maritime Organization (IMO) or 30 minutes when exposed to more severe conditions, as prescribed by UL 1709 standards. Typical designated fire zones include the regions in which are located engines or turbines or furnaces, any auxiliary power unit, fuel-burning heaters, and other combustion equipment intended for in transit use. For example, in aircraft, the combustion, turbine, and tailpipe sections of turbine engines must be isolated from the rest of the aircraft by a properly rated fire wall. In ships, the oil-burning furnaces and steam generators also must be isolated from the rest of the ship by a properly rated fire wall and overhead. In addition, substrates such as steel, aluminum, and many types of composites made of vinyl esters, polyesters, phenolics, and other types of resins, require a rated fire wall for the fire proofing of military installations, commercial buildings, and the like.
In most applications, current insulation blankets/insulation panels are impractical or provide reduced performance for many reasons, such as, heavy weight, thickness, or durability of the materials used, or the requirement of a top coating for surface finishing which adds a flammable top layer. In addition, spray-on fire proofing coatings are relatively difficult and time consuming to apply and to inspect, and are subject to cracking and peeling which then must be repaired or replaced frequently. This all adds up to increased installation costs, further maintenance costs and increased downtime for the aircraft and ships involved.
There remains a need for a fire retardant insulation blanket/insulation panel having the following desirable features of being thin and light weight; having high performance standards (such as meeting CG A60 or UL 1709 standards); a finished surface wall which requires no top coating; a minimal surface flame spread having a class A rating according to ASTM E84 standards; being easy to install which requires only simple butt joints and no reinforced joints and is non-toxic to humans in the virgin or combusted state.